Genotoxic Effects of Dracocephalum Lindbergii Essential Oil Assessed by Comet Assay: Dose-Dependent Increase in DNA Damage Markers

Abstract

Background: The essential oil of Dracocephalum lindbergii (Lamiaceae) contains bioactive compounds with potential therapeutic properties. Objectives: The present study evaluated the genotoxic effects of D. lindbergii essential oil. Methods: Essential oil was extracted from the plant using the Clevenger method and analyzed by gas chromatography-mass spectrometry (GC-MS) to determine its chemical constituents. Genotoxicity was evaluated in human umbilical vein endothelial cells (HLIVECs) using the comet assay by gel electrophoresis with fluorescent dyes. Intracellular antioxidant activity was assessed by measuring glutathione (GSH) levels and reactive oxygen species (ROS) generation. Absorption, distribution, metabolism, excretion, and toxicity (ADMET) properties of the main compounds in the essential oil were evaluated using an in silico approach. Results: The GC-MS analysis identified limonen40-yl-acetate as the predominant compound in the essential oil, accounting for 66362 of the total ion chromatogram (TIC). Unidentified compounds constituted 8.084 and 12350 TIC, indicating additional biologically active molecules. Minor constituents included monoterpenes such as limonene and d-3-carene (3.104 and 4.294 TIC, respectively), and the sesquiterpene germacrene (3.131 TIC), suggesting a chemically diverse extract. The comet assay demonstrated that the essential oil did not induce DNA damage at low concentrations but exhibited genotoxic effects at doses exceeding 10 og/mL. Furthermore, treatment with the essential oil led to increased intracellular ROS levels and reduced GSH, suggesting a potential oxidative stress-mediated mechanism underlying the observed DNA damage. Based on admetSAR predictions, limonene 10 yl acetate displayed drug-like behavior. Conclusions: The phytochemical profile of D. lindbergii essential oil indicates a predominance of monoterpenoid compounds, with limonen40-yl-acetate as the main component. While the MTT assay indicated weak toxicity on HUVEC cells with an ICso of 7073 pgimL, experimental data demonstrate that the oil induces concentration-dependent DNA damage, reduces intracellular antioxidants, and elevates ROS levels in HUVEC cells, indicating its genotoxic and oxidative potential in vitro at higher doses. These effects raise preliminary concerns about its safety, highlighting the need for additional research into in vivo toxicity, mechanisms of action, and the role of unidentified compounds to ensure responsible use in human medical and cosmetic applications.